This invention relates to a tamper evident device, especially for use with valuable items, so as to indicate if tampering has occurred. In particular, the invention relates to a tamper evident buckle.
When transporting or storing valuable items in containers it is important to be able to determine if the container has been tampered with. There are special xe2x80x9ccash boxesxe2x80x9d available for the storage or transport of cash or other small items. However, there are objects for which special security containers may not be available or for which tamper evident systems are not available.
It is known to provide simple seals for indicating tampering on containers such as an adhesive backed paper label in which an adhesive backed label bearing an authorised signature is secured across the closure. A more elaborate version of this type of tamper evident security device has been described in U.S. Pat. No. 5,568,951. The device includes a base and cover for securing two ends of a strap therein. The tamper evident means comprises a simple adhesive backed labelling strip affixed to the top surface of the cover and base. If the strip is tampered with to release the strap the damaged strip evidences the interference. This type of tamper evident strip is open to the same abuse as the more simple adhesive backed labels directly applied to the container to be sealed. It may be possible to lift the label from the cover by a variety of methods such as heat, steam or appropriate solvents without leaving a clear indication that tampering has occurred.
The present invention relates to tamper evident devices including a buckle with first and second parts adapted to be attached to a strap or belt and adapted to engage in a locking relationship. An enclosure is provided which surrounds the two parts and prevents their removal from each other while enclosed. A seal is provided which seals the enclosure and which must be broken to open the enclosure and release the two parts, whereby the seal cannot be re-used. Preferably the strap cannot be adjusted whilst the enclosure surrounds the two parts.
Accordingly, in one broad form, the invention provides a tamper evident buckle including:
a first part adapted to be attached to one end of an elongate strap;
a second part adapted to be attached to the opposed end of the strap;
said first and second parts including respective engagement means for releasably engaging the two parts together;
an enclosure movable between a first operative position wherein the first and second parts are freely engageable and disengageable and a second operative position wherein the enclosure substantially encloses the engaged together first and second parts; and
a seal including a main body, comprised of at least one component, and at least one deflectable member, wherein the seal is adapted to engage the enclosure in the second operative position and to prevent movement from the second operative position to the first operative position unless said seal is broken.
Preferably the enclosure includes a base and a cover. The cover may be hinged to the base or may be a separate component which engages with the base.
The first part may be permanently affixed at one end of the strap and the second part may be mounted on the strap for movement therealong.
When the two parts are engaged together and the enclosure is in the second operative position, preferably adjustment of the second part along the strap is prevented.
The first part and the base may be an integral component and the strap may be permanently affixed to the component.
The first part may include a female member having a passageway into which the second part passes. The second part may engage the internal surface of the passageway and/or one of the ends of the passageway. Preferably the second part includes two spaced apart arms having re-entrant barbs which pass through the passageway and engage the end of the passageway.
The seal may engage only the enclosure means or it may also engage the first and/or the second part. The main body of the seal may include at least two distinct components. The at least two distinct components may be joined by a frangible connection. The frangible connection may be in the form of a weakened bridge or hinge, or a plurality of same. The frangible connection may be formed by one of the components having a narrow construction at least in the regions of the join or joins between the components.
The second part preferably has a transverse body from which the two arms extend having an upper surface which is lower than the upper surface of the arms so that when engaged in the passageway an opening into the passageway is defined above the transverse body and between the two arms.
The cover may include a slot which aligns with the opening, so allowing the seal to be inserted into the opening.
The seal preferably has at least one arm which extends out of the plane of the opening to engage an inner face of the body.
The at least one arm may engage the inner wall or walls of the female member or may engage on one or more external end surfaces of the wall of the passageway.